The link was broken when I asked the question atleast.
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RichardNov 12 '12 at 13:28

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Nikon's web site isn't usually broken. But in any case, I think this question is okay here, because explanation of what exactly "Macro" might mean on a DSLR (as opposed to a point and shoot) is a valuable concept.
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mattdmNov 12 '12 at 13:56

2 Answers
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Close-up means photographing with a focus distance shorter than an arbitrary limit. (To further add to the confusion, most people will naturally see the distance from the subject to the frontmost lens element, while in photography distances are generally calculated from the film plane — the physical location, depth-wise, of the sensor in the camera)

Macro refers to having a magnification ratio (the proportion of the subject's actual size relative to that of the image as projected by the lens on the sensor) larger than another arbitrary limit, although a relatively more common definition involves 1:1 repoduction ratio and larger.

Since minimum focus distance is a function of the lens optics and the lens register (the distance from the outermost edge of the mount to the film plane) and so is the magnification ratio for a given distance, it is understandable how no function on the camera will be able to enable close-up photography without tricks such as increasing the lens register by moving the sensor, adding extension tubes or corrective elements.

Most confusion appears to be due to the misconcept perpetrated by most point and shoot cameras featuring a close-up enabling feature and calling it macro mode: all other factors being equal, a shorter distance implies a bigger ratio, but it is firstmost a feature enabling you to stick the camera at a few centimeters from your subject. On every interchangeable lens camera currently on the market, the camera doesn't automatically implement the above tricks: the "flower" mode is the full auto mode biased to prefer smaller apertures to enhance depth of field, which is gets critically smaller with magnification.